1 files changed, 24 insertions, 24 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index 75590572ff7a..9df8b861e18e 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -301,6 +301,27 @@ static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent)
         return parent;
 }
 
+/*
+ * Unhash a dentry without inserting an RCU walk barrier or checking that
+ * dentry->d_lock is locked.  The caller must take care of that, if
+ * appropriate.
+ */
+static void __d_shrink(struct dentry *dentry)
+{
+        if (!d_unhashed(dentry)) {
+                struct hlist_bl_head *b;
+                if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED))
+                        b = &dentry->d_sb->s_anon;
+                else
+                        b = d_hash(dentry->d_parent, dentry->d_name.hash);
+
+                hlist_bl_lock(b);
+                __hlist_bl_del(&dentry->d_hash);
+                dentry->d_hash.pprev = NULL;
+                hlist_bl_unlock(b);
+        }
+}
+
 /**
  * d_drop - drop a dentry
  * @dentry: dentry to drop
@@ -319,17 +340,7 @@ static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent)
 void __d_drop(struct dentry *dentry)
 {
         if (!d_unhashed(dentry)) {
-                struct hlist_bl_head *b;
-                if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED))
-                        b = &dentry->d_sb->s_anon;
-                else
-                        b = d_hash(dentry->d_parent, dentry->d_name.hash);
-
-                hlist_bl_lock(b);
-                __hlist_bl_del(&dentry->d_hash);
-                dentry->d_hash.pprev = NULL;
-                hlist_bl_unlock(b);
-
+                __d_shrink(dentry);
                 dentry_rcuwalk_barrier(dentry);
         }
 }
@@ -832,10 +843,8 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry)
         BUG_ON(!IS_ROOT(dentry));
 
         /* detach this root from the system */
-        spin_lock(&dentry->d_lock);
         dentry_lru_del(dentry);
-        __d_drop(dentry);
-        spin_unlock(&dentry->d_lock);
+        __d_shrink(dentry);
 
         for (;;) {
                 /* descend to the first leaf in the current subtree */
@@ -844,16 +853,11 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry)
 
                         /* this is a branch with children - detach all of them
                          * from the system in one go */
-                        spin_lock(&dentry->d_lock);
                         list_for_each_entry(loop, &dentry->d_subdirs,
                                             d_u.d_child) {
-                                spin_lock_nested(&loop->d_lock,
-                                                DENTRY_D_LOCK_NESTED);
                                 dentry_lru_del(loop);
-                                __d_drop(loop);
-                                spin_unlock(&loop->d_lock);
+                                __d_shrink(loop);
                         }
-                        spin_unlock(&dentry->d_lock);
 
                         /* move to the first child */
                         dentry = list_entry(dentry->d_subdirs.next,
@@ -885,10 +889,8 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry)
                                 list_del(&dentry->d_u.d_child);
                         } else {
                                 parent = dentry->d_parent;
-                                spin_lock(&parent->d_lock);
                                 parent->d_count--;
                                 list_del(&dentry->d_u.d_child);
-                                spin_unlock(&parent->d_lock);
                         }
 
                         inode = dentry->d_inode;
@@ -935,9 +937,7 @@ void shrink_dcache_for_umount(struct super_block *sb)
 
         dentry = sb->s_root;
         sb->s_root = NULL;
-        spin_lock(&dentry->d_lock);
         dentry->d_count--;
-        spin_unlock(&dentry->d_lock);
         shrink_dcache_for_umount_subtree(dentry);
 
         while (!hlist_bl_empty(&sb->s_anon)) {